Materials and Exporting to different formats
Material definitions can become very complex. Simple things like the Color, Specularity, Transparency can be exported to .obj (wavefront format). More complex material definitions which involve the texture stack can not be exported as .obj afaik. However, if you ask if exporting materials is possible "in principle", then the answer is "yes":

You can transport more complex materials by using FBX or Collada as transfer format. But beware, not even with these formats you can transfer the complete material definition. This is partially because the material properties are blender specific, and partially because the exporters have not (yet) implemented the full capabilities. 

I know that the Collada exporter allows to export materials with image textures in the texture stack. I guess the FBX exporter can do that as well (but this needs an approval)